Several reactions are known to occur in the linear sequence of basic myelin protein in the region of residues 95-115 of the bovine protein: the threonine at 98 and the serine at 110 can be phosphorylated by a protein kinase; the threonine at 98 can be glycosylated by an N-acetylgalactosaminyl transferase; arginine at 107 can be methylated by a methylating enzyme to give omega-monomethylarginine or omega-N-N'-dimethylarginine. Some or all of this reactivity may be involved in the function of the protein. It is proposed that each of these reactions can be studied using isolated peptides containing different areas of the 95-115 sequence. We have demonstrated that the synthetic peptide: Gly-Arg-Gly-Leu-Ser-Leu-Ser-Arg (residues 106-113) can be phosphorylated at serine 110 by a Cyclic-AMP dependent protein kinase (Daile, Carnegie and Young, Nature 257: 416-418, 1975). We have also demonstrated that the peptide Thr-Pro-Pro-Procan be glycosylated (Fed. Proc. 37: 1684, 1978). The specificity of the reactions will be studied by testing the reactions with analogs of the peptide. Solid phase peptide synthetic methods will be utilized in preparing the peptides. A chemical synthesis of alpha-N-acetylgalactosaminyl-O-Thr-Pro-Pro-Pro will be undertaken. The following radioactive compounds will be used in the assay; (32P)-ATP, S-adenosyl (1-methyl 14C)-methionine, and UDP-N-acetylgalactosamine (14C). Synthetic substrates for the N-acetylgalactosaminyl polypeptide transferase enzyme will be supplied to Dr. Colin Hughes of the British Medical Research Council, Mill Hill, England. He is setting up a wide panel of assays for investigation the involvement of glycosyl transferase in mental illness. The peptides will also be made available for testing their involvement in inducing experimental allergic encephalomyelits.